Method of and means for bending iron bars



1941- A. WAGENBACH 2,231,305

METHOD OF AND MEANS FOR BENDING IRON BARS Filed May 2'7, 1958 Patented Feb. 11, 1941 OFFICE 7 mi'rnon or AND MEA S Fon BENDING ,IRONBAByS. Anton Wagenbach. Wuppertal Elbei-Ielm;

, .-Germany.

Application May 27, 1938, Serial No. 210,457

r In- Germany May 10, 1937' 3 i Y 11 Claims. (oi. 153-45) g Application has been filed in Germany on a plan of the top of the improved bending ma- May 10, 1937. a

The known methods of, bending iron bars, particularly iron bars for use in reinforced concrete structures, permit only of bending tocomparatively small radii, as in these methods the iron has to be bent arounda former, for instance a bending pin having the required radius of curvature. If. considerable curvatures, that is [0 great bending radii are to be attained, the stationary formers or bending pins become very bulky and heavy and consequently the exchange of such formers is difli'cult and'cannot be car-' ried out by a' singleoperator: For this reason it has. been suggested to use, instead .of solid formers or bending pinabending segments hav- 1 ing the required length-of .arc, butthis does not solve the diiiicultieswhich arise; particularly in the case of radii of comsiderable size, say several metres, which are now required, particularly in connection with roadf building.

' Accordingto the invention 'these drawbacks 5 of the known methods are substantially avoided by mountingthefiron .to be'be'nt "between twoj "I 5 fixed points and 'gra'duallybending the'length of'ironlying betweenthese fixed points to the ,curved lever,constituting the former, by grad- ,uallyrolling. th curved. former upon the iron 1 bar. .This method .hafsthe' advantage that cur-H 5 vatures, such as, circular arcs' involutes or'other,

I shapes' ofanydesired si'gecan bent directly without'the' necessity of employing; as hitherto;

'veryflarge bendingldisos or blades and using heavy'and tinwieldy' bending rollers. According ;to-a pre'ferredmcde'of carrying out the method,

the curved former is constituted by a; one-armed leve'rpwhichis-adapted to be clutched to the" bending shaft of the bending machine, said shaftconstituting'at the same time one of the supports for the iron tobe bent. -The curved bendving lever is ;.preierably provided atboth ends withan ,opening -for insertion upon. the bending shaft, so thatl it maylbe selectivelyused either" for. right-hand a. deft-hand curvatures. ,The

50 other. fixed support for the iron to be bent may a be constitutedby. pi-ns adjustably mounted at the ends of the machine table or adjacent "projectingmembers fixed to the table. i

The invention is illustrated in the drawing b 55 a constructional example, the drawing showing :by .full 1 lines in the drawing.

then set-in motion and, due to the rotationoi the fierted into. the right handirack I 0. =arcs areto beproduced thanthe are upon" the chine. I

The table plate I of the machine is, in known manner, provided with one or more bending discs 2. Upon the end 3 of the main shaft of the bending machine, which projects above the 'bendingdisc 2, is fixed a segment-,shaped lever 4, which'is symmetrically formed and is provided at both ends with a suitable opening 5, so that it may, as indicated by dotted lines, be used also 10 for bending left-hand curvatures. Above the bending lever 4 there is mounted upon the shaft lifting of the iron bar during the bending. At

both ends ofthe machine tablel there are provided toothed racks 9 and ID- respectively, 20 each formed with a longitudinal slot H for the reception of 'supportingr'ollers l2. Thisarrangemerit; enables the "supporting rollers H I o be fixed in any desiredjposition. The bars Sand iii are arranged at the same level as the bending 2 discs2; i

'Beforecommencing the bending operation, the iron rod :1; is placed in thepo'sition indicated The machine is driving shaft carrying on its end 3'the bending disc .2 and the bending lever 4, the bending lever I rolls with ,itsfperipheryr which has the curva- -,tu re'to. be ini parted to the iron bar, upon the 'iron' bar, and the latter being supported by the fixed. roller l2, and the pin 3, will therefore receive the shape indicated by'dotted lines. As

soon as thebending lever thas reached the end position'-"indicated' by. dotted lines, thedriv'e of "the shaft is "stopped in a manner known per se 40 by means' of a stop inserted into one of the holes of the bending disc. "As indicated by dot- ,ted 1ines.-':thebending operation' may also take place inthe opposite direction, whereby a lefthand' curvaturewill be imparted 'to a foarfixed between"E the shaft .3 andthe'supporting roller in- If longer bending lever;4,'=the; above described bending operation may be several times repeated upon the samejiron bar, the several bends following each "other and constituting one very long bend.

I claim:

1. In a bending machine for bending iron bars, more particularly iron bars for reinforced concrete structures, the sub-combination of: a table; a bending disc rotatably mounted therein; a shaft for turning said disc having an end projecting upwards from said disc; a curved former adapted to be fixed to said projecting shaft; a clamping yoke fixed to said shaft and also fixed to said disc for holding the bar to be bent; and an adjustable stop upon said table for holding the remote end of the bar.

2.. In a bending machine for bending iron bars, more particularly iron bars for reinforced concrete structures, thesub-combination of: a table; a bending disc rotatably mounted therein; a shaft for turning said disc having an end projecting upwards from said disc; a curved former adapted to be fixed to said projecting shaft; a clamping yoke fixed to said shaft and also fixed to said disc for holding the bar to be bent; and an adjustable stop upon said table for holding the remote end of the bar, said adjustable stop being constituted by a transverse member fixed to the table and by a roller adjustably mounted thereon. 7

3. In a bending machine for bending iron bars, more particularly iron bars for reinforced concrete structures, the sub-combination of a table; a bending disc rotatably mounted therein; a shaft for carrying and driving said bending disc, said shaft having an end portion pro-" je'cting upwards from the table and a bending disc; a pin mounted uponsaid bending disc; a clampingyoke mounted upon the projecting 7 end upon the shaft and having a means for clamping said yoke to said pin; a curved former adapted to be fixedto the top end of said shaft for rotation therewith; and an adjustable stop upon said table; the rod to be bent being located at one point between the top end of the shaft and the pin of the table and supported at the remote end by said adjustable stop.

4. In a bending machine for bending iron bars, more particularly iron bars for reinforced concrete structures, the sub-combination of: a table; a bending disc rotatably mounted therein and having a number of holes for the insertion of a pin; a pin inserted into one of said holes; a shaft for driving said bending disc having an upper end projecting from said disc; a curved former inserted upon said shaft end for rotation therewith; a clamping yoke inserted upon said shaft end and enclosing said pin and having means for clamping to said pin; two bars one at each side of the table, each bar being provided with a slot; and a supporting roller slidable in said slot and fixable therein in any desired position, said curved former being symmetrically shaped and having at either end a hole for fixing to said shaft end.

5. -A process for bending iron rods by means of a rocking bending member having a curved rod contacting surface shaped to the bend to be produced in the. rod, said process consisting in supporting a rod between two spaced points one of which is adjacent the rocking point of the bending member and the other of which is spaced therefrom, and rocking said member to cause its rod contacting surface to progressively engage the rod from the support adjacent the rocking point toward the other supporting point.

6. A process fortbending iron rods by means of a rocking bending member having a curved rod contacting surface shaped to the bend to be produced in the rod, said process consisting in supporting a rod between two spaced points one of which is adjacent the rockingpoint of the bending member and the other of which is spaced therefrom, and rocking said member to cause its rod contacting surface to progressively engage the rod from the support adjacent the rocking point toward the other supporting point, the resistance to bending being progressively increased on the rod.

'7. Process for bending iron rods particularly those used in reinforcing concrete by means of an oscillating curved piece, in which first the iron rod'is placed between two fixed points and the turning point for the curved-piece, and next the part of the iron rod lying between the fixed points is bent outwardly and away from the turning point of the curved piece by means of oscillating the curved piece, whereby the curved piece beginning at one fixed point rolls on the iron rod toward the other fixed point.

8. Process for bending iron rods particularly those used in reinforcing concrete by means of an oscillating curved piece, in which first the iron rod is'placed between two fixed points and the turning point of the curved piece, and next the part of the iron rod lying between the fixed points is bent outwardly away from the turning point of the curved piece and rolls on the iron rod beginning at one fixed point toward the other fixed point with increasing lever arm.

9. Process for bending iron rods particularly those used in reinforcing concrete by means of an oscillating curved piece, in which first the iron rod is placed between two fixed supports and a support for the curved piece serving as pivot and next through the oscillations of the curved piece the part of the iron rod lying between the two fixed supports is bent outwardly by the support of curved piece, whereby the curved piece beginning at the one fixed'support rolls over the iron rod toward the other fixed support.

10. Process for bending iron rods particularly those used in reinforcing concrete by means of an oscillating curved piece which bends outwardly and away from the pivot point of the curved piece, the iron rod placed between two fixed points and the pivot point of the curved piece.

11. Process for bending iron rods and especially those for reinforcing concrete by means of an oscillating curved piece which bends outwardly and away from the pivot point of said curved piece, the iron rod placed between two fixed points and the pivot point of the curved piece, the use of a curved piece of symmetrical form which has on both ends meansfor looking on its pivot axis and which starting from one pivot point rolls over the iron rod toward the other fixed point.

ANTON WAGENBACH.

due to the rolling. action of the bending member 

